Stabilized peanut butter and method of producing the same



United States Patent 3,129,102 STABILIZED PEANUT BUTTER AND METHGD 0FPRGDUQING THE SAME Judson H. Smders, Wyoming, Ohio, assigner to TheProcter & Gamble Company, Cincinnati,-0hio, a corporation of Ohio NoDrawing. Filed Apr. 9, 1962, Ser. No. 185,881 6 Claims. (Cl. 99-128)This invention relates to peanut butters. More specifically, it relatesto a combination of ground peanuts and peanut oil to which has beenadded a particular type of vegetable oil material thereby providing aproduct which has unusual stability and tolerance to a wide variety ofprocessing conditions.

Peanut butters are customarily made by roasting and blanching rawpeanuts and then grinding them. The resulting product is a pastymaterial which is a mixture of peanut particles and oil which has beenreleased from the cellular structure of the nuts during the grindingoperation. If this product is allowed to stand for a period of time, theoil will separate from the product and will form a separate layer on topand a rigid crumbly mass underneath.

It is known that the addition of hydrogenated oils, such as hydrogenatedpeanut oil, will tend to stabilize peanut butter so as to prevent anexcessive amount of oil separation by formation of a crystal matrixwhich lends rigidity to the mass and prevents settling of peanutparticles. It has been found however, that the addition to peanut butterof a large enough quantity of highly hydrogenated fats such ashydrogenated peanut oil, to stabilize the product substantiallycompletely against oil separation, will tend to make the peanut butterexcessively firm at ordinary temperatures of use. As a result theproduct is ditficult to spread, has a waxy taste, and tends to cling tothe roof of the mouth when it is eaten.

Another disadvantage of the use of known hydrogenated fat stabilizerssuch as hydrogenated peanut oil is the wide variance of product qualitywhich results from varying the temperatures at which the material isprocessed. In grinding peanuts to make peanut butter the temperature ofthe product will increase to about 160 F. or higher. Stabilizingmaterial is added during the grinding step or while the product is at anelevated temperature. In common commercial practice the product is thenrapidly chilled, customarily using a device such as a scraped wall heatexchanger (chiller), to a temperature below the freezing point of atleast a portoin of the fat solids present in the product. The chilleroutlet temperatures may range from as low as' about 70 F. to as high asabout 120 F. Variations in the chiller outlet temperatures frequentlyoccur even during plant runs, and conventional peanut butter stabilizersat any given level of usage have a widely varying eifect on thefirmness, stability, and eating quality of the final product, dependingupon the exact chiller outlet temperature. Such variations may be causedby fluctuations in stock and coolant flow rates and inlet temperatures.

Yet another disadvantage of the use of known hydrogenated fatstabilizers is the wide variance of product quality caused by variationsin mechanical agitation of the partially formed crystal matrix followingchilling.

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Any physical working of peanut butters stabilized by hydrogenated fatsafter they are chilled, but prior to the time they are packaged, willinfluence greatly the firmness and degree of stabilization of the peanutbutter. Such working may involve agitation during completion of thecrystallization which occurs subsequent to the rapid chilling step. Flowthrough extended piping will cause some agitation of the product. Sometypes of filling machines are provided with agitated hoppers which aredesigned to maintain the chilled peanut butter in pumpable conditionuntil packaged.

Delay between chilling and packaging can also cause problems due to therapid firming of peanut butters made from commonly-used stabilizers.Non-uniform residence time in equipment, especially where there is a lowvelocity flow in piping, will cause serious non-uniformity in productwhen hydrogenated peanut oil is used as a stabilizer.

It has now been found that the use of a hydrogenated rapeseed oilstabilizer in peanut butter will greatly minimize these prior artproblems.

Accordingly, it is an object of this invention to provide a stabilizedpeanut butter composition which can be processed under a wide variety ofconditions of temperature without adverse aflect on the product quality.

A further object is to provide a peanut butter in which only a verysmall amount of stabilizer need be present.

Yet another object is to provide a peanut butter which can toleratechanges in agitation and/or delay between the chilling and packagingsteps.

Other objects and advantageous features will be apparent from thefollowing detailed description.

In general, the product of this invention is a peanut butter productcomprising a homogeneous mixture of particles of peanuts and peanut oil,and having uniform ly dispersed therein a stabilizing amount of ahydrogenated rapeseed oil stabilizer having an iodine value not greaterthan about 10.

The peanut butter can be prepared by conventional methods such asroasting and then grinding the peanuts. Likewise, the hydrogenatedrapeseed stabilizer can be introduced into the peanut butter by knownprocesses. These include adding it to the nuts in the grindingequipment, or thoroughly and homogeneously dispersing it in the hotground peanut butter. Preferably the stabilizer should be in melted formwhen added at this stage. Other additives are commonly admixed during orfollowing the grinding step. The peanut butter is then chilled to atemperature sufliciently low that at least some fat solids will form toproduce a crystal matrix. Preferably this temperature should be belowabout F.

It is understood, however, that the invention is not to be limited toany particular manner of making peanut butter or introducing thestabilizer.

A preferred hydrogenated rapeseed oil stabilizer for this invention israpeseed oil hydrogenated to an iodine value of not more than about 10.If the rapeseed oil is hydrogenated to a higher iodine value the peanutbutter in which it is incorporated will have a decreased tolerance .tovariations in processing conditions and the level required forstabilization will be undesirably increased.

The amount of stabilizer should range from about 0.5% to 5.0%, by weightof peanut butter, and preferably from about 1.5% to 3.0%. If less thanabout 0.5% of the stabilizer is present the peanut butter will have anundesirable amount of oil separation due to insufiicient stabilizationwhen the product is stored at room temperature. If more than about 5.0%of the stabilizer is used, the product will be too firm and will have awaxy taste. In general, larger amounts of stabilizer within the aboverange are required for higher processing temperatures.

Another stabilizer within the scope of this invention is a hydrogenatedand superglycerinated rapeseed oil having an iodine value not greaterthan about 10. The superglycerination can be performed by well-knowntechniques such as reacting hydrogenated rapeseed oil with glycerine inthe presence of a suitable catalyst. Preferred products generallycontain about to 40% monoglyceride, 20% to 40% diglyceride, and 20% to40% triglyceride. These materials do not have as great a tolerance tovariations in processing conditions as does the hydrogenated rapeseedoil.

Also included within the term hydrogenated rapeseed oil stabilizer is acomposition containing at least about 90% hydrogenated rapeseed oilmonoglyceride. This can be formed, for example, by a superglycerinationof rapeseed oil hydrogenated to an iodine value of about 10, followed byseparation, as by distillation, to obtain a fraction containing at leastabout 90% monoglyceride.

Peanut butter of this invention, incorporating the hydrogenated rapeseedstabilizer, can contain other hydrogenated or unhydrogenated fattytriglycerides, or bydrogenated superglycerinated fats or fattymonoglycerides. Such materials include soybean oil, cottonseed oil andpeanut oil, either in natural form or in a hydrogenated and/ orsuperglycerinated form. The exact amount to be used will vary dependingupon the desired properties of peanut butter and the processingconditions which are to be used. A specific additional fatty material iscottonseed oil hydrogenated to an iodine value not greater than about10, and which may be present in amounts up to about 1.0% by weight ofthe peanut butter.

Mixtures of the various hydrogenated rapeseed oil stabilizers can beused.

Other additives such as salt, lecithin, and sweetening agents such assucrose, dextrose, and honey, can also be present in the peanut butter.

The following examples will serve to illustrate the invention withgreater particularity.

EXAMPLE 1 Peanuts were roasted, blanched and cleaned to remove alldebris. The peanuts were then fed into a peanut butter mill consistingof two vertical parallel circular plates, one fixed and one rotating.The inner surfaces of the plates were equipped with burrs or teeth, witha small clearance between the plates. The peanuts were fed into thecenter of the plates and were forced out the sides in the form of finepeanut particles and oil. In separate runs various stabilizers in groundsolid form, each with about 1% salt and 2% dextrose, by weight of thefinal peanut butter, were fed into the peanut stream entering the mill.The ground product at a temperature of about 160 F. was fed into arecirculating system to thoroughly mix the ingredients.

The peanut butter with stabilizer was then fed into a second mill, whichconsisted of two horizontal circular carborundum plates, where it wasfurther ground to finely divide the peanuts, salt, and dextrose. Duringthis grinding step the temperature rose to about 180 F. The peanutbutter was fed to a surge tank, and then passed through a scraped-wallchiller in which it was rapidly cooled down to the desired temperaturesunder test. It was then packaged in jars with the aid of conventionalpacking equipment.

The packaged peanut butter was stored for two months at a temperaturewithin the range of 85 to 90 F. and then examined. There was no oilseparation, and all of 4 the peanut butters were readily spreadable. Thestabilizers and chiller outlet temperatures used are shown in Table I.

Table I Percent Chiller Stabilizer 1 By Weight Outlet oi Peanut Tempera-Butter ture F.)

l Stabilizer ARapeseet1 oil hydrogenated to an I.V. of 8. Stabilizeri361: fIl'glXljUfG of: 94% Stabilizer A; 6% cottonseed oil hydrogenatedto an As can be seen by the above, satisfactory peanut butters can bemade over a wide range of chiller outlet temperatures.

EXAMPLE 2 Under processing conditions comparable to those of Example 1,it was found that peanut butter stabilized with Stabilizer B of Example1 could be held as long as 15 minutes with slot agitation, in a fillinghopper after chilling and before packaging, without becoming too firm totolerate the destructive flow attendant upon packaging which woulddisrupt the crystal matrix sufficiently to cause instability. Usingconventional filling equipment a similar product made with hydrogenatedpeanut oil began to stiffen noticeably after 3 minutes, and after 5minutes was too firm to tolerate the flow attendant upon packaging.

EXAMPLE 3 The process of Example 1 was repeated using only 1.5% ofStabilizer 'B. Using chiller outlet temperatures ranging from 80 to l03E, products were made which were stable against oil separation andpossessed good properties of spreadability, eating quality andappearance.

EXAMPLE 4 Peanuts were roasted, blanched and ground in a mill similar tothat used in Example 1. The resulting peanut paste, at a temperature ofabout F., was placed in an agitated, jacketed tank in which it wasmaintained at a temperature of 160 F. Stabilizers were melted and addedto the paste at a level of 2.75%, by weight. 1.5% salt and 2% dextrose,both by weight, were added, and the mixture was agitated for one hour toform a homogeneous blend. The stabilizers used were rapeseed oilhydrogenated to an iodine value of about 10 and peanut oil hydrogenatedto an iodine value of about 10.

The blends were passed through a scraped wall chiller, chilled totemperatures as specified in Table II, and then packaged in jars.Samples of the packed products were held at 70 F. for 24 hours.

Penetration measurements were then made of the various samples, asindicated in Table 11, using a Precision Universal Penetrometer made byPrecision Scientific Company, Chicago, Illinois. In this test a conicalstainless steel needle was dropped onto the surface of the peanut butterfrom a height two inches above the surface. The needle tapered 8 off ofcenter and was inch in diameter at the top and had a point diameter ofinch. The needle and the shaft on which it was mounted weighed 47 grams.A penetration value of to 300 indicates a product having goodspreadability and resistance to oil separation. A penetration value ofless than 175 indicates too firm a product, while a penetration value ofmore than 300 will indicate a product which is susceptible to oilseparation, particularly under ordinary shipping conditions.

Table II Penetration (mm.)

Chiller Outlet Temperature F.)

Rapeseed Peanut Stabilizer Stabilizer As can be seen from these data,when varying chiller outlet temperatures were used there was a widevariation in product containing peanut stabilizer whereas the productmade with rapeseed stabilizer was substantially uniform.

What is claimed is:

1. A peanut butter comprising a homogeneous mixture of particles ofpeanuts and peanut oil, said peanut butter having dispersed therein fromabout 0.5 to 5.0%, by weight of peanut butter, of a hydrogenatedrapeseed oil stabilizer having an iodine value not greater than about10.

2. -A peanut butter according to claim 1 wherein the stabilizer israpeseed oil hydrogenated to an iodine value of 8.

3. A peanut butter according to claim 1 wherein the stabilizer issuperglycerinated hydrogenated rapeseed oil.

4. A peanut butter according to claim 1 wherein the stabilizer containsat least about hydrogenated rapeseed oil monoglyceride.

45. A peanut butter according to claim 1 which contains additionally upto 1.0%, by weight of peanut butter, of cottonseed oil hydrogenated toan iodine value not greater than about 10.

6. The method of increasing the resistance of peanut butter to oilseparation and improving resistance to product quality change withvariation in processing conditions which comprises adding to said peanutbutter from about 0.5% to 5.0%, by weight of peanut butter, of ahydrogenated rapeseed oil stabilizer having an iodine value not greaterthan about 10, said addition being carried out by thoroughly mixing saidstabilizer with said peanut butter in a melted condition and thenchilling the peanut butter-stabilizer mixture to a temperaturesufficiently low that at least some fat solids will form to produce acrystal matrix.

References Cited in the file of this patent UNITED STATES PATENTS11,058,738 Ellis Apr. 15, 1913 1,395,934 Stockton Nov. 1, 1921 1,926,368Brown Sept. 12, 1933 2,721,803 Ginn Oct. 25, 1955 P040510 UNITED STATESPATENT OFFICE CERTIFICATE OF CORRECTION patent NO 3 129, 102 Dated April14, 1964 Inveritofls) Judson H Sanders It is certified that errorappears in the above-identified patent and that said Letters Patent arehereby corrected as shown below:

I Column 5, line 2 (that is, in the heading of Table II? h) should be(mm./lO)

dllmw Am SEALED (SEAL) Attcst:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Ir.

Commissioner of Patents Attesting Officer

1. A PEANUT BUTTER COMPRISING A HOMOGENEOUS MIXTURE OF PARTICLES OFPEANUTS AND PEANUT OIL, SAID PEANUT BUTTER HAVING DISPERSED THEREIN FROMABOUT 0.5% TO 5.0%, BY WEIGHT OF PEANUT BUTTER, OF A HYDROGENATEDRAPESEED OIL STABILIZER HAVING AN IODINE VALUE NOT GREATER THAN ABOUT10.